Driver assistance device

Abstract

A driver assistance device comprises a travel route calculator, a danger zone identifier, an information acquisitor, a speed determiner, and a speed controller. The travel route calculator is configured to calculate a travel route to a destination set by an occupant of a vehicle. The danger zone identifier is configured to identify a danger zone on the travel route. The information acquisitor is configured to acquire, from at least one preceding vehicle traveling ahead on the travel route, travel and road surface information at a time when the preceding vehicle has traveled in the danger zone. The speed determiner is configured to, based on the travel and road surface information, determine a safe-travel speed at which the vehicle can travel in the danger zone safely. The speed controller is configured to control, with the safe-travel speed, a travel speed of the vehicle when the vehicle travels in the danger zone.

The invention claimed is: 
     
         1 . A driver assistance device comprising:
 a travel route calculator configured to calculate a travel route to a destination set by an occupant of a vehicle;   a danger zone identifier configured to identify a danger zone on the travel route;   an information acquisitor configured to acquire, from at least one preceding vehicle traveling ahead of the vehicle on the travel route, travel information and road surface information at a time when the at least one preceding vehicle has traveled in the danger zone;   a speed determiner configured to determine, based on the travel information and the road surface information, a safe-travel speed at which the vehicle can travel in the danger zone safely; and   a speed controller configured to control, based on the safe-travel speed, a travel speed of the vehicle when the vehicle travels in the danger zone.   
     
     
         2 . The driver assistance device according to  claim 1 , wherein the at least one preceding vehicle is a vehicle other than an emergency vehicle. 
     
     
         3 . The driver assistance device according to  claim 2 , wherein the speed determiner is configured to, upon determining the safe-travel speed, use the travel information and the road surface information of the at least one preceding vehicle that has traveled in the danger zone within a predetermined time before the vehicle reaches the danger zone. 
     
     
         4 . The driver assistance device according to  claim 3  comprising a travel determiner configured to perform, based on the travel information and the road surface information, determination on whether traveling in the danger zone is dangerous,
 wherein the travel route calculator is configured to calculate a travel route that avoids the danger zone when the travel route calculator has received a result of the determination from the travel determiner that traveling in the danger zone is dangerous. 
 
     
     
         5 . The driver assistance device according to  claim 1 , wherein the speed determiner is configured to, upon determining the safe-travel speed, use the travel information and the road surface information of the at least one preceding vehicle that has traveled in the danger zone within a predetermined time before the vehicle reaches the danger zone. 
     
     
         6 . The driver assistance device according to  claim 5  comprising a travel determiner configured to perform, based on the travel information and the road surface information, determination on whether traveling in the danger zone is dangerous,
 wherein the travel route calculator is configured to calculate a travel route that avoids the danger zone when the travel route calculator has received a result of the determination from the travel determiner that traveling in the danger zone is dangerous. 
 
     
     
         7 . A driver assistance device comprising one or more processors and one or more memories communicably connected to the one or more processors, wherein the one or more processors are configured to:
 calculate a travel route to a destination set by an occupant of a vehicle;   identify a danger zone on the travel route;   acquire, from at least one preceding vehicle traveling ahead of the vehicle on the travel route, travel information and road surface information at a time when the at least one preceding vehicle has traveled in the danger zone;   determine, based on the travel information and the road surface information, a safe-travel speed at which the vehicle can travel in the danger zone safely; and   control, based on the safe-travel speed, a travel speed of the vehicle when the vehicle travels in the danger zone.